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Earthquake Simulation ProjectMany systems in nature are examples of non-linear driven dissipative systems and can exhibit complex behavior. Over the past one hundred years physicists have developed a well-defined theoretical framework to describe systems in equilibrium. However, there is still much work needed to understand the behavior of non-equilibrium systems, the simplest of which are nonlinear driven dissipative systems. Earthquake fault systems belong to this class of systems and exhibit simple power-law scaling in both space and time, such as empirical Gutenberg-Richter law of the frequency-size distribution of the seismic moment (P(M) =a M^{-b}) with the exponent b between 1.5 and 2.0, and the modified Omori's law of temporal decay of aftershocks (dN_as/dt = 1/t_0(1+t/t_0)^p) with p close to 1. The Burridge-Knopoff spring-block model (BK model) was the first one proposed to do numerical and analytical investigations containing the essential physics of faults (Seismol. Soc. Am. 57, 341 (1967)). Physicists began to explain the scaling of earthquakes around 1980s by borrowing concepts that have evolved in statistical physics. The main concepts have been applied are self-organized criticality of Pak and Tang et al. (J. Geophys. Res. 94, 15635 (1989); Phys. Rev. Lett. 59 381 (1987)), and spinodals and nucleation of Klein and Rundle et al. (Phys. Rev. Lett. 78, 3793 (1997); Phys. Rev. E 60, 1359 (1999)).I am simulating earthquakes using molecular dynamics in collaboration with Professor Harvey Gould at Clark University, and Professor Bill Klein at Boston University. The main model we are using was proposed by Burridge and Knopoff (BK) in 1967. Other models we are using are cellular automaton (CA) versions of spring-block model, such as the Olami-Feder-Christensen (OFC) and the Rundle-Jackson-Brown (RJB). The main goals are (1) investigate the mean-field behavior of the BK model with long range interaction; (2) verify the mean-field behavior of the long range OFC model; (3) look for the scaling in the long range OFC model; (4) study the phase transition of long range OFC model induced by the loading velocity. I will post my results here for anyone interested in my research on earthquake simulations. Please feel free to send any comments and suggestions to me.
Progress Reports| about | research | publications | resume | photos | links | site map | If you have any suggestions, please send e-mail to jcxia@physics.clarku.edu. Updated on 05 January 2005 |
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